The invention relates to flue systems for gas-fired water heaters.
It is known to weld or otherwise metallurgically bond fins inside a water heater flue tube to enhance heat conduction through the walls of the flue tube. It is also known to hang removable baffles in a flue tube to turbulate the exhaust gases flowing through the flue tube.
However, known systems often do not meet the current gas-fired water heater regulations relating to efficiency and construction for facilitating cleaning, and many of those water heaters that do meet the current regulations will not meet the next, more strict regulations to be enacted. For example, under today""s regulations, the flue of a water heater has to be cleanable to remove soot and other buildup that may be hazardous. Many known flue systems were not designed to be easily cleaned, and therefore may not meet this regulation.
For example, one known flue tube fin arrangement includes a plurality of small fins extending radially inwardly into the flue tube from the flue tube wall. Soot can collect on these small fins, and the small fins are not easily cleaned with a brush. Another example is a twisted fin positioned within the flue tube. A twisted fin is not easily cleaned because a cleaning brush would have to be twisted to follow the contour of the fin.
The present invention provides a flue system for a water heater. The flue system permits the combustion characteristics of the water heater to be tuned or adjusted. The system also permits relatively easy cleaning of the flue. The flue system includes a fin that is metallurgically bonded to the flue tube, and a removable baffle having at least one turbulation surface. The combustion quality of the water heater is adjusted by adding or removing baffles and by adjusting the turbulation surfaces of the baffles. The fin may be a cruciform-shaped fin, a pair of V-shaped fins, or a plurality of straight fins. Preferably, the fins divide the flue tube into flue chambers extending substantially parallel to the longitudinal axis of the flue tube, and the removable baffles are hung in selected flue chambers.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.